OBJECTIVES: 1. Proposed to study the secretion of oxytocin in lactating women during early postpartum period. For this study lactating women as well as non-lactating women will be used. The non-lactating women will be used while these subjects give milk by bottle to their babies to see the physiological effect oxytocin release and to compare with the lactating women. 2. Proposed to study the oxytocin level during normal menstrual cycle in comparison with FSH, LH, Prolactin, Plasma Estrone, Estradiol and Progesterone.